1. Field of the Invention
The invention concerns the display of information in a digital computer system and more particularly concerns the display and analysis of information about a very large number of entities.
2. Description of the Prior Art
Users of computer systems have access to enormous quantities of primary information. For example, it is easy for the user to display any line of any text file which the user is permitted to read. The computer has also made it possible to compute or gain access to all kinds of secondary information, that is, information about the primary information, for example, it is easy to determine how many times a given word appears in a collection of text files and where the occurrences are in the text files. If the information is available in the computer system, it also easy to determine things like who wrote each line in the text file or when the line was written.
A consequence of the easy availability of large amounts of primary and secondary information has been the development of many kinds of information analysis systems. These systems use the secondary information to select items of the primary information, and thereby permit study of the primary information. An example of such an information analysis system is the text data base, which permits a user to search for information in a collection of text files.
A problem in the use of such information analysis systems has been the manner in which the information in the information analysis system is displayed. Typically, the user can display the secondary information which he is using to access the primary information and can display the actual primary information. The display generally provides little or no information about the relationship between the secondary information and the primary information. For example, the user of a text data base can see the expression he is using to search the text data base, can see how many "hits" there were, i.e., how many items in the text data base contained words which satisfied the search expression, and can see a screenful of lines from any of the items upon which there was a hit. What the user does not have is an overview of the relationship between the hits and the items in which they occur or the relationship between the hits and the entire text data base.
In broad terms, the prior-art displays do not provide a context for the evaluation of the hits. Such a lack of context is particularly important in situations where the context is known to the user and is important for the evaluation of the primary information. For example, in a text data base, the occurrence of hits in certain texts may have more significance than their occurrence in others, and even the locations in the texts at which the hits occur may be important.
The information display apparatus of the parent application solved the above problem by displaying information about a very large number of entities in a fashion which preserved the context of the entities, permitted the discovery of interesting subsets of the entities, and permitted detailed study of the entities. The present patent application discloses improvements which substantially increase the usefulness of the information display apparatus.